Hello everyone, my name is Ted and i am proud to be one of the few Diamante owners out there :)
About the car. Its a 1999. Has 29,6** miles and was previously owned by a 70 year old woman that drove it once a week. Everything works (except fog lamps :P ) and it drives like a dream. However, there seems to be something that runs on my mind.
I start the car early morning to get to school, i always let it idle for about a minute or 2 before i go, and i drive it real easy especially in the morning.


The Problem

When i accelerate, i hear some sort or growl just around 1200-1350 RPM and then its gone. I dont expect it to be a transmission thing, because if i let it shift into second, and i accelerate slowly, it makes the same noise in that RPM range.
when the car is almost completely warmed up, it only does it between 1200 and 1250 RPM. (i acellerated and listened slowly and carefully for this). Once its completely warmed up, nothing. Oil has been changed, just before i bought it so i dont know if it did that from before.
Its not even too noticable i just wouldnt want something too severe to happen in the future.

Thanks in advance for the help.
I will be making some home made mods that i will share with the community when i find a way around homework for a couple hours. but as of now, its completely stock!

is it driveshaft / CV joints

check this link
Part two faults and diagnosis http://www.aa1car.com/library/cvjoint2.htm

next brakes or rotor warp ??

Hmm, definitely strikes a thought...
When it was purchased, it was in need of an allignment, but i did not know how long it was like that for. If for example the allignment of the wheels were in a way that put strain on the CV joints, would it damage them?

Last question, how is it that when its completely warmed up, there is no sound?

Purchasing a repair manual this weekend. I'm gettin to to know this whip :thumbsup:

Is it when cold warm up driving? I might know wut it may be the heat sheild under the car on the exhaust , particularly the catalytic converter which is located underneath the car around the area where the center console starts . So in the morning it would be audible on cruising before shift changes and in a specific certain RPM range . Ive seen in it in a few cases. Areas where people live or have lived in cold snowy areas , near wgere salt water or etc , or sumthing that could have passed under the car and moved or bent the inner or surrounding heat shield around the exhaust .

Once did i have to replace the catalytic converter for this low end growl.

does not seem like its right before shift changes or anything. As for heat shields, i looked and all of them seem fine except for one at the very front as the image shows.

i apologize for the quality, this was taken with my phone, but yeah, i am hoping to take a recording of me driving in the morning where you can possibly hear it.

I also thought, 9 year old car. yes 29k miles, but can timing belt already get old enough that it might need to be replaced?

30k Tuneup very soon but im not going to give up 700 to the dealership when theres something wrong for the car, plus about 160 for a diagnosis.
do yer own fluid flushes :)

The second generation Diamante makes a characteristic growl noise when cold around the 1200 RPM range. This is due to the AC belt. There is a TSB on this that recommends removing the idler pulley and using a shorter belt, but both of my Diamante's have the new setup (a 1999 and a 2002) and they still make the noise when cold. The TSB referrs to it as a metallic/rubbing noise, but it is more of a growl as the speed passes through a small range around 1200 RPM.

Here is the TSB:

The TSB number is TSB-00-11-004:

"PURPOSE
This bulletin contains information concerning the deletion of the air conditioning compressor/generator belt idler pulley.

BACKGROUND INFORMATION
The air conditioner compressor/generator drive belt idler pulley was deleted from Diamante vehicles beginning with early 2000 model year production. This change was made as a product improvement to reduce noise. You may remove the idler pulley from all 1997 - 2000 model year vehicles that were originally fitted with this pulley under the following circumstances:

1. A customer complaint of a metallic/rumblingnoise at approximately 1200 r/min.
2. Whenever the drive belt requires replacement.

AFFECTED VEHICLES
1997-2000 Diamante
NOTE: The deletion of the A/C compressor/generator idler pulley was scheduled for the beginning of 2000 model year production, however, some very early production 2000 models may have this pulley installed as original equipment.

WARRANTY INFORMATION
A/C Compressor/GeneratorDrive Belt Idler Pulley Removal and Belt Replacement
Nature Code: 802 Cause Code: 990
Labor Operation No. 55314200 Time Allowance: 0.3 hr.
Warranty Coverage: 36 months/36,000 miles.
Special Warranty Information: Normal warranty procedures apply."

So you're saying if i replace the drive belts i should be good? Doesnt bother me unless it is prone to damaging my diamante in the long run.

The procedure calls for removing and discarding the AC/Alternator belt idler pulley and replacing the belt with the new shorter belt. I would recommend staying with a Mitsubishi belt from the dealer's parts department. Before replacing the belt, you could verify that the sound is coming from the belt by removing the belt temporarily and driving the car. You just won't have AC and the alternator won't be charging, so just test drive it for a few minutes to check the noise.

The only other noise that could sound like what you describe is the growl that comes from the small catalytic converters that are immediately after each exhaust manifold. They would only be present if your 1999 has a California spec'd emission system. You can check that by looking at the exhaust manifolds to see if there are small catalytic converters, about the size of a shoebox, on each side of the engine between the exhaust manifold and the place where the exhaust pipes join together under the engine. That growl is normal. If you do not see the cats, your 1999 has a Federal spec'd emission system and the noise is not coming from the cats.